diff --git a/compress.go b/compress.go
index 1d02cdd2..50fc5ab0 100644
--- a/compress.go
+++ b/compress.go
@@ -24,7 +24,7 @@ type compressor struct {
 
 // Compress 压缩
 func (c *compressor) Compress(content []byte) ([]byte, error) {
-	if c.writeBuffer.Cap() > internal.Lv3 {
+	if c.writeBuffer.Cap() > internal.Lv4 {
 		c.writeBuffer = internal.NewBuffer(nil)
 	}
 
diff --git a/protocol.go b/protocol.go
index 3c3a684a..1a5f40e2 100644
--- a/protocol.go
+++ b/protocol.go
@@ -15,6 +15,8 @@ func (c Opcode) IsDataFrame() bool {
 	return c <= OpcodeBinary
 }
 
+// WebSocket Event
+// OnError and OnClose will not both be called
 type Event interface {
 	OnOpen(socket *Conn)
 	OnError(socket *Conn, err error)
diff --git a/updrader.go b/updrader.go
index 973bd3b5..3a4e34cb 100644
--- a/updrader.go
+++ b/updrader.go
@@ -69,6 +69,7 @@ func handshake(conn net.Conn, headers http.Header, websocketKey string) error {
 }
 
 // Accept http protocol upgrade to websocket
+// ctx done means server stopping
 func Accept(ctx context.Context, w http.ResponseWriter, r *http.Request, eventHandler Event, config Config) (*Conn, error) {
 	config.initialize()